Before a dental implant can be implanted in the jaw bone of a patient, a jaw bore must be drilled into the jaw bone of the patient into which the dental implant is thereafter placed or screwed. It is of critical importance for the cosmetic quality and the durability of the dental prosthesis supported by the dental implant that the spatial position, the orientation and the depth of the implant bore in the jaw are exact with respect to the planning.
For an exact drilling of the jaw bore, a drilling jig is described in WO2010/097405 A1 which comprises an individualized part individually adapted to the respective jaw of a patient, for example, by an impression taken before. The drilling jig can be set on the relevant jaw of a patient in a form-fitting manner and in a manner reproducible with respect to the spatial position and orientation. The drilling jig has a guide channel that is in exact alignment with the planned jaw bore when the drilling jig is set on the patient's jaw. The guide channel serves to guide the jaw drill with which the jaw bore is drilled into the jaw bone.
The guide channel in the drilling jig is formed using an auxiliary jig that can be produced at a location remote from the drilling jig. In producing the auxiliary jig, an auxiliary bore is first drilled into an auxiliary jig body of plastic material into which an auxiliary drilling sleeve of metal is inserted. Both the drilling jig and the auxiliary jig have respective coupling structures that correspond to each other and are complementary to each other, the structures providing for a defined spatial position of the drilling jig and the auxiliary jig coupled thereto. The spatial position and orientation of the auxiliary jig correspond to the spatial position and orientation of the planned jaw bore so that the auxiliary bore and the auxiliary bore sleeve are in exact alignment with the planned jaw bore if the drilling jig were set on the patient's jaw and the auxiliary jig were set on the drilling jig.
Using the auxiliary jig set on the drilling jig, a dentist can use an appropriate drill to drill a guide bore in the plastic drilling jig body, which is aligned with the with the auxiliary bore sleeve. The auxiliary jig is thereafter removed from the drilling jig body, whereupon a metal guide sleeve is inserted, e.g., screwed, into the guide bore. The guide bore forms the guide channel for drilling the jaw bore into the jaw bone.
The finished drilling jig is subsequently set on the patient's jaw. The jaw bore for the dental implant is then drilled into the patient's jaw bone using a jaw drill, the drilling being performed in alignment with the guide sleeve or the guide channel of the drilling jig. The required depth of the jaw bore in the jaw bone is here more or less left to the subjective judgment of the dentist.